Liquefied gas tank



Oct. 29, 1935. Y P. s. ENDAC OTT LIQUEFIED GAS TANK Filed May 8, 1955 ATTORNEYS. I

' Patented Oct. 29, 1935 PATENT OFFICE LIQUEFIIED GAS TANK Paul S. Endacott, Detroit, Mich, assignor to Phillips Petroleum Company, Bartlesville, 0kla., a corporation of Delaware Application May a, 1933, Serial No. 670,046

3 Claims.

This invention relates to improvements in tanks particularly well adapted for use in the storage and utilization of liquefied gas, such as propane.

Heretofore it has been the most general practice to service customers with liquefied gas for domestic and analogous purposes, according to what is generally known as the one-drum and the two-drum systems.

According to the one-drum system, the customer has on his premises a drum, hereinafter called a tank, for storage of liquefied gas and other equipment for the utilization of the gas. An example of'such a tank is shown in Patent No. 1,897,163, granted February 14, 1933 on the invention of Rosswell W. Thomas. The customers equipment is generally serviced by the vendor transporting and introducing into the tank a supply of the liquefied gas. In order to make reasonably sure that the customer will have at all times a ready supply of the liquefied gas in storage, without attention on the part of the customer to the equipment, trips are made periodically by truck to the customers equipment. By including a number of customers on a route, the service man may with more or. less regularity, say every month, attend to the requirements of the customers, without the necessity of attention on the part of the customers. By a weighing operation the service man determines, first, the

quantity of liquefied gas consumed and for which the customer is generally billed, and, second, the quantity he has introduced into the tank to replenish the supply in storage. This system has many advantages mainly among which is the low investment in tanks, since only one tank is provided as a part of the customer's equipment and it remains on the customers premises indefinitely. This is in contradistinction to the two-drum system, where at least two tanks ordinarily form a part of the customers equipment, altho gas is generally being drawn from but'one of the tanks at a time.

The two-drum system involves a servicing operation on the part of the customer as well as the vendor. The customer, when he has utilized all of the liquefied gas in one tank, goes to the equipment and, by the manipulation of valves brings into use the second filled tank. He then notifies the vendor, as by mail or telephone, to come for the empty tank and replace it with a filled tank. The service man is thus required to either make by use of a truck, a special trip to the customer's equipment or include it as a stop if travelling a route in order to substitute a filled tank for that which has been emptied and to be in readiness to be drawn upon when the occasion arises. The two-drum system, it will be seen has high investment requirements, that is, at least two tanks for each customer, and expensive distributing costs. 5

Both the "one-drum and two-drum systems are necessarily restricted to relatively small geographical areas which have high concentration of population beyond the gas mains, for it is unprofitable for the vendor, or too expensive for the purchaser if these servicing trucks must travel a considerable distance from the vendor's service station or depot.

The present invention is particularly well adapted for, but not necessarily limited to use where the customer operates the liquefied gas storage and utilization equipment on his premises and looks after the transportation of the empty or partially empty tank to a supply depot or station, and a filled tank from such depot or station to his equipment. In doing so the customer may use any suitable vehicle for transportation of the tank and its contents. For instance, the family automobile may be used and since, in the outlying rural sections trips are frequently made to the more populated sections where there are various supply establishments, this transaction may take place while on other errands. Thus liquefied gas may bemade available to those located in sections where the cost or servicing of the customer's equipment according to the one-drum and two-drum systems above referred to, would be prohibitive.

The principal objects of the present invention are, to provide as a single unit, a tank having a chamber for a major supply of liquefied gas which may serve as a source of supply, for the average family, for several days or a month or more, ac cording to the length of time the equipment is in operation and the number and kind of appliances in use during such operation; and also a chamber for a minor or reserve supply of 1iquefied gas which may be drawn upon when the major supply is depleted and until there is an opportune time to replace the tank thus used with a run charged tank.

Another object of the invention is to provide such a. tank which may be suspended for weighing, signalling and other purposes, having the chambers so arranged that a pipe or tube affording communication between one of the chambers and the control means for egress of the vapors arising from the liquefied gas will pass thru the other chamber and serve also to brace the tank, e pecially when in a suspended position.

\ crown portions of the means D, means Other objects and advantages of the invention will appear in the following detailed description, taken in connection with the accompanying drawing, forming a part of this specification, and in which drawingz- Figure 1 is a view partly in elevation and partly in vertical section thru liquefied gas storage and utilization equipment, including a tank constructed according to the present invention. talligure 2 is an enlarged top plan view of the Figure 3 is an enlarged bottom plan view of the Figure 4 is a detail view in vertical section thru the upper portion of the tank and showing control means associated therewith in elevation.

'In the drawing, where similar characters designate similar parts thruout the views, A is a rigid support, such as the wall of a building; B a tank constructed according to the present invention; C a lifting and weighing or signalling device secured to support A and associated with tank B; D control means for the egress of gas from tank B; E means for reducing the pressure of the vapors finding exit from tank B thru control means D; F a detachable connection between means E and tank B; G a conduit line between the means E and. customers appliances where the gas is to be burned; and H a suitable housing for the device C and other parts of the equipment.

' The tank B preferably comprises a cylindrical body 5 having a dome-shaped top wall 6 and av bottom wall 1, providing a major compartment or chamber 6 for liquefied gas; and a relatively shorter cylindrical body 9 having a dome-shaped top wall l0, the'cylindrical body 9 being welded or otherwise secured as at ii to the upper portion-of cylindrical body with top wall 6, a minor compartment or chamber l2 for'liqueiied gas. Top wall I0 is provided with a major chamber outlet boss l3 and a minor chamber outlet boss I, a pipe or tube i5 affording communication between the major compartment or chamber 3 and boss l3. This pipeor tube l6 may be welded as at i1 about an opening 18 in the top wall 6 and have screw threaded engagement, as at l 9 with the interior of boss I3, 50' that the pipe extends thru minor compartment or chamber l2 and is secured to the heads 6 and In. It is preferred to locate pipe or tube is at the dome-shaped top walls at the longitudinal axis of the tank so that when the tank B is suspended, as shown in Figure 1 above the ground 20, the tank will hang substantially vertical and this pipe or tube l5 thru its connection with the top walls will assist in distributing the load or force of gravity acting upon the tank and its contents to various parts of the tank instead of to merely the top wall l0. It is also to be observed that this pipe or tube 15 strengthens the top wall 6 when the pressure of the liquefied gas in compartment i2 is superior to that in compartment 8, or vice versa.

In the example shown, the lifting and weighing device C is associated with the tank 13, being operatively connected to the latter thru control E for reducing the pressure of the vapors before entering the conduit line G, and the detachable connection F between means E and control means D. The preferred details of this lifting and weighing device are shown in so-pending application for patent of Paul S. Endacott entitled "Load lifting and weighing devices filed May 8, 1933, Serial No, 670,045.

bring into 5 and providing, together rigid with housing.

Briefly it comprises a bracket 2i secured to support A in any suitable manner; a hanger 22 vertically movable with respect to the bracket 2i; a screw 23 secured to hanger 22 and vertically movable with respect to bracket 2|; a nut 24, for, 5

screw 23, rotatably mounted upon bracket 2|, whereby the screw may be fed upwardly or down-- wardly according to the direction of rotation of the nut; and, a scale 25 supported by hanger 22. The scale 25 preferably comprises a sleeve beam section 26; a stem beam section 21 slidably re-' ceived by section 26; a poise 28 rigid with stem section 21 and a suspension stirrup 29, the beam section 26 being pivotally suspended by hanger 22. By moving the stem section 21 and poise 26 inwardly or outwardly with respect to section. 26, the quantity of liquefied gas in the tank B may be determined. It is preferred to extend stem section 21 of the scale beam exteriorly of housing H where it, together with the poise 28 may act 20 as a signal, visible from quite some distance. As an example, the section 21 may be placed to indicate, by downward movement of the poise 28, a small quantity of liquefied gas remaining in the major compartment 8, so that the attendant may 25 use the liquefied gas in the reserve compartment i2 before the major supply of liquefled gas is depleted. The control means D preferably comprises a main valve 30 having an upwardly extending in.- 30 ternally screw threaded outlet fl, this valve having screw threaded engagement with the boss IS; a reserve valve 32 having screw threaded engagement with boss I; a by-pass'tube or pipe'33' between valves 30 and 32; and mainv and reserve 35 relief valves 33 and 34, respectively. By opening ,valve 30, vapors arising from the liquefied gas in major compartment 8 may find egress thru pipe i5, valve 30, and its outlet port 3!. By opening valve 32 vapors arising from the liquefied gas 40 in minor compartment l2 may find egress thru valve 32, by-pass 33', and outlet port 3i. Under normal conditions, however, valve 32 is not opened until nearly all of the liquefied gas in major compartment 6 has been used, or if attention has not 45 been paid to the equipment and no gas is available at the consumer's equipment, where the gas is burned, valve 32 may then be opened to utilize the reserve supply until an opportune time arrives to take the tank 13, together with any lique- 5 fied gas that may remain in the minor compartment I2, to the service depot or station and obtain a filled tank for further use.

Referring now to the means for reducing the pressure of the vapors finding-,exit from tank 13 55 thru control means D and detachable connection F, it preferably consists of any one of the many conventional pressure reducing regulators, whereby the high pressure vapor is reduced to a pressure of say one pound per square inch or less -a no pressure suitable for use in the usual appliances, such as gas stoves, lighting fixtures, etc. pressure reducing regulator is preferably suspended from stirrup 29, by an eye bolt 40. At its lower end it is connected to control means D 55 by detachable connection F which may comprise a compression nozzle I having connection with valve outlet 3!, this compression nozzle being placed or removed with respect to outlet 3| by means of a wrench l2. Q a

The conduit line Grincludes a pipe length N H, one end portion bein capped as at 46 and the other end portion having communication with a service line 46 thru union 41 or any other suitable coupling. The low presring 50 welded or otherwise secured to its bottom wall 1 upon which the tank may rest when not suspended, and a protecting collar preferably oval in plan, mounted upon the dome-shaped top wall In, about the crown thereof, and surrounding the control means D. The collar 5| may be joined to top wall II) in any suitable manner, such as by welding as indicated at 52, and is provided with drainage ports 53 at its ends, adjacent its juncture with the top wall |0,--the lowest portions of the compartment defined by the collar for eflicient drainage.

The housing H is also secured to support A and preferably encloses at least a portionof the tank B, as well as device C, and other units of the equipment which should be protected from the weather.

One of the principal advantages resulting from the provision of a tank to contain a major and minor supply of liquefied gas, is the elimination of the necessity for more than one gas tank on the customers premises at any one time, thus materially reducing the investment in customers tanks, which is always a major factor in equipment for dispensing liquefied gas. Also, when only one tank need be on the customer's premises, there is less possibility of tanks becoming lost, un-

duly subjected to the elements, or creative of hazardous situations.

By having the minor compartment in the same unit that supplies the major compartment, the assembly may be made much more compact than by having either two tanks of the same size, or a large and a small tank where only a small reserve supply is desired.

In practice, the consumer may not need to use the liquefied gas in the reserve chamber since the scale 25 may be used as a signal, as previously described thus enabling the consumer to substitute a filled tank while making a trip to the vicinity where the service depot or station is located, and at a time when gas will not be required at the consumers appliances. If, however, attention is not paid to the signal device, and all of the gas arising from the liquefied gas in the major compartment 8 is used, the consumer may then open valve 32 and use so much of the reserve supply as may be necessary to permit use of the appliances until he has an opportunity to take the tank to the service depot or station.

The devices shown at 60 in Figures2, 3 and 4 i are for use in securing the tank to a vehicle, such as an automobile, and are disclosed in detail in co-pending application of Paul S. Endacott entitled "Liquefied gas transporting apparatus", filed July 31, 1933, Serial No. 683,091.

What is claimed is:

1. An elongated ciosed'tank for containing liquefied gas under superatmospheric pressure to be 5 vaporized for use in a fuel consuming appliance, comprising an elongated body, a top wall, a bottom wall, and a transverse partition nearer the top wall than the bottom wall to divide the tank into a lower major compartment and an upper minor compartment, a pipe extending longitudinally of the tank at its longitudinal axis, secured to 'said partition, open to said major compartment, passing through said minor compartment and secured to the top wall, affording an outlet for vapors from said major compartment and means coaxial with said pipe and connected to said top wall of the tank from which the tank may be suspended.

2. An elongated closed tank for containing liquefied gas under superatmospheric pressure to be vaporized for use in a fuel consuming appliance, comprising an elongated body, a top wall,

a bottom wall, and a transverse partition nearer 1 the top wall than the bottom wall to divide the tank into a lower major compartment and an upper minor compartment, said top wall having an upstanding outlet boss at its central portion,

a pipe extending longitudinally of the tank at its longitudinal axis, secured to said partition, open to said major compartment, passing through said minor compartment and secured to said boss affording an outlet for vapors from said major compartment and means coaxial with said pipe and connected to said outlet boss from which the tank may be suspended.

3. An elongated closed tank for containing liquefied gas under superatmospheric pressure to be vaporized for use in a fuel consuming appliance and adapted to be normally suspended from its top wall in an upright position, comprising a cylindrical body having a top wall and a bottom wall providing a major compartment for liquefled gas, a second cylindrical body co-axial with and welded to the upper portion of said first mentioned body, said second cylindrical body being relatively shorter in height than said first mentioned cylindrical body and having a top wall to provide an upper minor compartment for liquefied gas, and a pipe co-axial with said cylindrical bodies, welded to the first mentioned .top wall, extending through said minor compartment, and having a screw threaded connection with said second mentioned top wall to afiord an outlet for vapors from said major compartment and to join said first and second mentioned top walls.

PAUL S. ENDAC'OTT. 

